# CVE-2017-8493: Windows Security Feature Bypass Vulnerability

CVE-2017-8493 is fixed in 15 products on 1 platform, first by KB4022714, released June 13, 2017. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2017-8493
- Priority: Routine
- CVSS: 5.6 (Important)
- EPSS: 0.0146
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Vendor exploitability assessment: Exploitation Less Likely
- Published: Jun 13, 2017
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2017-8493

## Description

<p>A security feature bypass vulnerability exists when Microsoft Windows fails to enforce case sensitivity for certain variable checks, which could allow an attacker to set variables that are either read-only or require authentication.</p> <p>To exploit this vulnerability, an attacker could run a specially crafted application to bypass Unified Extensible Firmware Interface (UEFI) variable security in Windows.</p> <p>The security update addresses the vulnerability by correcting security feature behavior to enforce case sensitivity for certain variable checks.</p>

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Microsoft | Windows 10 Version 1511 for 32-bit Systems | 10586.962 | [KB4022714](https://patchblox.com/security/data/fix/microsoft/kb4022714.md) | Jun 13, 2017 |
| Microsoft | Windows 10 Version 1511 for x64-based Systems | 10586.962 | [KB4022714](https://patchblox.com/security/data/fix/microsoft/kb4022714.md) | Jun 13, 2017 |
| Microsoft | Windows 10 Version 1607 for 32-bit Systems | 14393.1358 | [KB4022715](https://patchblox.com/security/data/fix/microsoft/kb4022715.md) | Jun 13, 2017 |
| Microsoft | Windows 10 Version 1607 for x64-based Systems | 14393.1358 | [KB4022715](https://patchblox.com/security/data/fix/microsoft/kb4022715.md) | Jun 13, 2017 |
| Microsoft | Windows 10 Version 1703 for 32-bit Systems |  | [KB4022725](https://patchblox.com/security/data/fix/microsoft/kb4022725.md) | Jun 13, 2017 |
| Microsoft | Windows 10 Version 1703 for x64-based Systems |  | [KB4022725](https://patchblox.com/security/data/fix/microsoft/kb4022725.md) | Jun 13, 2017 |
| Microsoft | Windows 10 for 32-bit Systems | 10240.17443 | [KB4022727](https://patchblox.com/security/data/fix/microsoft/kb4022727.md) | Jun 13, 2017 |
| Microsoft | Windows 10 for x64-based Systems | 10240.17443 | [KB4022727](https://patchblox.com/security/data/fix/microsoft/kb4022727.md) | Jun 13, 2017 |
| Microsoft | Windows 8.1 for 32-bit systems |  | [KB4022717](https://patchblox.com/security/data/fix/microsoft/kb4022717.md) | Jun 13, 2017 |
| Microsoft | Windows 8.1 for 32-bit systems |  | [KB4022726](https://patchblox.com/security/data/fix/microsoft/kb4022726.md) | Jun 13, 2017 |
| Microsoft | Windows 8.1 for x64-based systems |  | [KB4022717](https://patchblox.com/security/data/fix/microsoft/kb4022717.md) | Jun 13, 2017 |
| Microsoft | Windows 8.1 for x64-based systems |  | [KB4022726](https://patchblox.com/security/data/fix/microsoft/kb4022726.md) | Jun 13, 2017 |
| Microsoft | Windows RT 8.1 |  | [KB4022726](https://patchblox.com/security/data/fix/microsoft/kb4022726.md) | Jun 13, 2017 |
| Microsoft | Windows Server 2012 R2 |  | [KB4022717](https://patchblox.com/security/data/fix/microsoft/kb4022717.md) | Jun 13, 2017 |
| Microsoft | Windows Server 2012 R2 |  | [KB4022726](https://patchblox.com/security/data/fix/microsoft/kb4022726.md) | Jun 13, 2017 |
| Microsoft | Windows Server 2012 R2 (Server Core installation) |  | [KB4022717](https://patchblox.com/security/data/fix/microsoft/kb4022717.md) | Jun 13, 2017 |
| Microsoft | Windows Server 2012 R2 (Server Core installation) |  | [KB4022726](https://patchblox.com/security/data/fix/microsoft/kb4022726.md) | Jun 13, 2017 |
| Microsoft | Windows Server 2016 | 14393.1358 | [KB4022715](https://patchblox.com/security/data/fix/microsoft/kb4022715.md) | Jun 13, 2017 |
| Microsoft | Windows Server 2016 (Server Core installation) | 14393.1358 | [KB4022715](https://patchblox.com/security/data/fix/microsoft/kb4022715.md) | Jun 13, 2017 |

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Data as of 2026-11-07T18:46:35Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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